Goggle Construction Generally
Sport goggles, such as are often used for skiing, cycling, snow-boarding, motorcycle and ATV riding, paint-balling, or standard-issue military goggles used primarily for military ground operations, typically have comprised a plastic frame or body and a clear plastic, or polycarbonate, see-through lens. Sometimes the plastic body has further been comprised of an anterior body interconnected to a posterior body, the foremost portion of the anterior body being designed for attachment to, carrying and positioning of the lens a comfortable distance from a user's eyes. The posterior body has comprised a foam rubber interface on the most posterior portion thereof for comfortable positioning of the body on the user's face around and defining the field of vision for the user's eyes. Such conventional goggles have further comprised an elongated, elastomeric strap attached at either end thereof to corresponding ends of the anterior body for the purpose of holding the goggles on the head, or helmet, of the user by stretching the strap around the back of the head, or helmet, with the goggle positioned in opposing fashion on the face of the user. It has generally been accepted and understood among goggle wearers that different colors of lenses have been advantageous for different lighting and weather conditions.
The Need for Easily Interchangeable Lenses in Goggles
Earlier conventional goggles have not provided for interchangeable lenses. Not only has this resulted in a much less useful goggle as changing lighting conditions through the day have rendered a current goggle unsuitable for more easily distinguishing variations in terrain, especially snowy terrain of mostly a single color often having only slight shadows on the surface thereof to determine the presence of variations, but where the lens of the goggle has become damaged, or broken, such goggles have required replacement of the entire goggle.
More recently, conventional goggles have allowed for replacement of a damaged or broken lens, or replacement of a lens that is no longer suitable for changed lighting conditions. In such goggles, the body has comprised a flexible, but resilient, molded material forming a relatively deep vertically-oriented groove, often together with a plurality of notches on the lens matched with pegs in the groove for alignment and retention purposes. The notches and matched pegs have been designed to receive and hold the peripheral edge of the lens in a vertically-oriented fashion in the groove and to retain the lens in proper orientation on the pegs relative to the body.
When a user has desired to remove such a lens, they have pulled the flexible body members apart, disconnecting the notches and otherwise disassociating the lens from the groove in the body. Replacement with a different color lens has involved a reverse process of aligning the edge of the lens, and its notches, with their associated groove and pegs, first fitting an upper, or alternatively lower, portion of the lens into its associated groove and pegs, and then fitting the opposite portion of the lens into its associated groove and pegs. This process has been time-consuming and cumbersome, making it difficult for a user to easily interchange lenses, so much so that many have determined to not make an attempt to change the lens in the open, but rather to use a lens that has provided multi-purpose, though not ideal, use for most lighting conditions. Alternatively, where users have shown the patience necessary to have repeatedly changed lenses, these goggle bodies have lost some resiliency, broken, or cracked, due to repeated stressing of the bodies, and this has led to a lack of a engagement between the lens and the body.
Responsive to the difficulties of interchanging lenses for these types of goggles, there have been developed goggles having articulated frames designed for opening and closing to allow easier changing to lenses adapted for changed conditions. An example of such a frame is provided by U.S. Pat. No. 5,815,235, to Runckel, for Ski Goggles With Pivotal Frame Members For Interchanging Lenses. Similarly, published US Patent Application No. US20110225709A1, to Saylor et al., for Eyewear With Interchangeable Lens Mechanism, has facilitated the interchanging of lenses of such goggles with a biased outrigger, gate or latch for securing the lens relative to the goggle, the lens being further held in a proper orientation by one or more engagement members aligned with an aperture, or apertures, in the lens.
The Need for Anti-Fog Means in Goggles
Goggles are known to have become obscured with moisture when temperature and relative humidity conditions inside of the space defined between the goggle body and the user's face and eyes have been such that a dew point has been reached and condensation has formed like a “fog” on the inner surface of the goggle. This typically has happened when a colder inner surface of the goggle lens has come in contact with a now warmer and more humid area enclosed within the goggle body. There are many possible conditions which may lead to fogging of a goggle, since the dew point of the inside of the lens is affected by varying temperature, moisture, pressure and ventilation conditions. One common example of fogging has occurred when a person who has been skiing, cycling, hiking or engaging in other strenuous activity, stops moving as quickly as before, reducing the amount of air flow over the surfaces of the goggle, such that temperature differentials between the inner surface of the goggle and the now warmed and moist air within the goggle caused by the physical exertion and the enclosed space of the goggle have caused fogging.
Another example of fogging involves a significant increase in activity, increasing the amount of moisture and heat trapped within the goggle, primarily from perspiration and also from a higher incidence of exhaling moist warm air that is associated with such physical exertion. In such a case there has existed a greater imbalance in temperature between the inner surface of the goggle lens and the warm, moist air now trapped within the goggle, causing condensation and resulting fogging of the inner surface of the goggle lens.
Thus, fogging is a very common problem with goggles and this has occurred in various situations involving temperature extremes, and particularly warmer temperatures caused by perspiration and respiration entering within the goggle enclosure and which are warmer relative to colder temperature conditions outside of the goggle body. Of course this problem has ranged from being annoying to the user, to presenting a very dangerous situation where the user's field of vision has been greatly diminished while the user has been traveling at high speeds among fixed obstacles, such as trees, widely varying terrain such as bumps, cliffs, or other participants, or the user has otherwise been unable to clearly see an intended target or an enemy combatant. The problem of fogged goggles has resulted in injury and even death among goggle users.
Responsive to this common, annoying and even dangerous condition, great attention has been paid to solutions to the problem of fogging of goggles. For instance, numerous efforts have been made to increase the amount of passive airflow into the goggle. Examples of such may be found in US Patent Application Serial No. 20050193478 to Hussey, for Goggle Attachment System, and U.S. Pat. No. 6,665,885 to Masumoto, for Goggles.
Despite best efforts to produce a goggle that utilizes passive air-flow means for defogging the lens of the goggle, there are often present conditions which have rendered passive air-flow means of de-fogging ineffective. Such conditions have overwhelmed the ability of the passive means to overcome the temperature and humidity differentials presented by exertion by a user in cold, icing conditions or accumulation of snow clogging ventilation means. Also, sometimes a user's clothing, especially such as scarves or face masks, have impeded intended airflow of such goggles, rendering them ineffective.
As a result, there have even been developed goggles with active, personal fans to ventilate the enclosed space within and the inner surface of the lens of the goggle to mitigate the conditions leading to fogging. An example of such a system has been provided in U.S. Pat. No. 5,452,480, to Ryden, for Ski Goggles. One problem of such a device is that it does not necessarily overcome icing, snow accumulation or other blockage of outer goggle vents, thus rendering such a system less effective.
Regardless of the exact causes of fogging of a goggle in a particular situation, it has become understood that sufficient heating of the inner surface of the lens of the goggle comprises an effective means of removing fog from the lens and preventing further fogging. Accordingly, there have been developed various means of actively heating the inner surface of the goggle lens. One such means has comprised the placement of wires, or a resistive film surface, on the inner surface of the goggle lens, which wires or resistive surface have been attached to an electrical power source such as a DC battery carried on the goggle headband or jacket of the user in order to provide sufficient power to heat the lens. Examples of such a method of heating the lens of the goggle have been disclosed in U.S. Pat. No. 4,868,929, to Curcio, for Electrically Heated Ski Goggles, U.S. Pat. No. 5,459,533, to McCooeye et al., for Defogging Eye Wear, and Published US Patent Application Serial No. US20090151057, to Lebel et al., for Reversible Strap-Mounting Clips for Goggles.
Thus, while there have been devised independent solutions to a need for easily interchanging the lens on a sport or standard-issue military goggle and the need for maintaining such a goggle fog free, there yet exists a need for a sport or standard-issue military goggle that provides not only an easily interchangeable lens system, but also provides an active, effective means of heating the lens to prevent fogging. In particular, there exists a need for an efficient and effective means of both releasably attaching the lens of a goggle to its body and therefore preferably allowing for efficient, simultaneous interconnection of the lens to a source for heating of the lens when necessary to prevent fogging. Ideally, such a system would be easy to operate, even with a gloved hand, and would be provided in a goggle that is relatively inexpensive to manufacture, and is thus affordable, for sporting and standard issue military ground operation applications.